Hey guys, I did a 60% water change a few days ago for my 12 gallon, and my tank is undergoing a mini cycle *I think*. I checked my ammonia, nitrite, and nitrate levels, and all but my nitrites are at optimum levels, at 0 ppm for ammonia and 10-20 ppm for nitrates. However, my nitrites are at 2 ppm. I did 2 water changes of 25% each so far, but the nitrite is still at 2 ppm. I added tetra safestart today, so hopefully it'll help. I also did replace my 8" air stone with a sponge filter, so potentially I lost some colonies of bacteria that were growing on that. However, my fish are not stressed at all, and aren't showing any signs of nitrite poisoning. They're eating fine, swimming fine, not gasping for air, not getting any brown spots, no rapid gill movements, and no lethargic actions. Also, all the snails and shrimp I have show no signs of stress. I did add activated carbon and purigen to help clear my water up of tannins, and I did clean my old filter cartridge *in a bucket of old tank water, shook it loose of any organic material left on it*. Maybe I shook too hard and took out the good bacteria colonies?

Anyways, I'm just wondering if this really is a mini-cycle, or a false reading from my API liquid tests. Thanks!

zof

05-19-2011 10:50 PM

Test your tap water that will tell you at least if its coming from your tap or tell you to further investigate your test kit. I wouldn't think you would have lost that much bacteria from from replacing your filter sponge and cleaning your cartridge but it might have happened, until you figure out what it is keep doing water changes or at least keep adding water conditioner if it says on the bottle that it detoxifies nitrites as the detoxification will usually only last 24-48 hours.

Also a couple of questions, what do you have stocked in this tank? How old is your test kit(you can find printed numbers towards the top of the bottle)? And what water conditioner are you using?

excal88

05-20-2011 12:21 AM

I have 9 cory cats and 3 platys in my 12 gallon *its overstocked, but I do maintenance 2-3 times weekly* I know its not my tap water as I tested it before, and I actually have been using RO water mixed with a little bit of tap whenever I do my water changes. My test kit is new, got it 2 months ago and the date is still well out of expiration. The weird thing also was that up until I cleaned the cartidge and added the sponge filter, I also added activated carbon and purigen. The purigen was suppose to get rid of nitrites in the water, but lo and behold it jumped up. I have since removed both carbon and purigen to allow things to settle.

I'm using prime as my conditioner, so I'll be adding some of that to my tank. I'll check again later tonight, but its just really odd for it to jump like this. Up until 2 days ago the water parameters were perfect, so really weird.

AbbeysDad

05-20-2011 10:58 AM

It's hard to say but it sounds like you may have made enough changes to upset the beneficial bacteria balance in your aquarium. Just do sufficient water changes until things settle down.
Moving forward, perhaps minimizing changes at one time may help.

excal88

05-20-2011 03:52 PM

Yea, I think so too. Things seem to be stabilizing today, so we'll see how things go in the next few days. Thanks guys!

excal88

05-22-2011 04:41 PM

Ok, update. So it seems that my tank is officially going under another cycle; checked my ammonia levels after a few days and its at .50. Did a water change, so we'll see how things go. Kind of fustrating that I washed off all the bacteria on my filter media, but thats how things go. Hopefully my sponge filter will kick in soon....